AOk.
Why don't we allow FREE Govt/Council approvals for all "energy upgrades" to existing buildings?...or even no approvals for many upgrade categories?

In Oz so often we use AC when we ought be just opening windows and/or using blinds etc.
I presume many people would prefer natural breezes or just ventilation in buildings much of the time. We ought only turn on AC in buildings when necessary. Also attenuating AC systems is so often poor and this wastes heaps of power.

I think our leaders could create an example by setting the thermostat to 26C in various houses of parliament. Note the wearing of dark suits even in hot weather. That's not leadership it suggests that AC is a reward for 'making it'.

No doubt if time-of-use smart meters become widespread those deemed frail will get all the aircon they want. As with medical marijuana in the US I suspect this will be exploited. If wet bulb temps exceed 38C then productive work will be impossible without refrigerative and dehumidifying aircon. More power draw.

Those who say PV will power aircon should note hot conditions often persist well after dark. Again the grid. I believe the answer is a low tariff for say 500w for thermal comfort. Wise people will have a small insulated room without plasma TVs. Stay in that room when it is over 40C or below 10C and use the low powered heating or cooling appliance.

I realised climate change was a threat when I was a teenager, so my adult life has been marked by eliminating unnecessary emissions. I don't have a car, and I've never used air conditioning. We can't afford it.

Older people who have had air conditioning at work for decades seem to shy away the most from facing the changes they need to make. They had already formed their habits before they realised those habits were unsustainable. Now, turning off (or even down) the air conditioning appears to be off the agenda - even in an architecture firm designing houses to be more sustainable.

The shift in attitudes and habits needed to kick air conditioning and car use are huge where they are already entrenched. The challenge is in demonstrating that we don't need those things.

Good piece. In Australia there's also been growing bodies of 'desert knowledge' involving CSIRO and CRCs in recognition that more of us around the world will be living in that sort of climate in the future.
On another note, people in air conditioned offices have been proving for years they're incapable of making good decisions for the 'outside world', so turning off the AC may well turn a few brains on.

Great article Tim, would be very interested to learn more about your work on alternatives to AC in SE Asia.

I'd like to suggest that we urgently need to add the climate impacts of the leaked refrigerants we use for the air conditioning of our buildings and vehicles to the list of purposes for which a public debate needs to be opened up concerning AC.

Atmospheric concentrations of the most common refrigerant HFC R134a are growing at over 10% p.a., and every kilogram of this gas equates to between 1.4 and nearly 4 tonnes of CO2-e, depending on how it’s measured (with 100 year or 20 year GWP figures – but for a gas with an atmospheric lifetime of 14 years, the 20 year GWP metric should be more relevant). Left unchecked, the climate impact of the hydrofluorocarbons will grow from around 2% now to around 9-19% by 2050 – these projections can only be avoided by determined action in the next few years to make more sustainable refrigerant choices.

For example, about 30% of the ‘bank’ of refrigerant in use in Australia is the ozone depleting and powerful greenhouse gas HCFC R22 with a carbon kick of 2 to 5 tonnes per kg in round numbers (GWP100/20 = 1810/5160). Imports of this gas are being phased down over the next 2 years to a ‘service tail’ of 45 tonnes out to 2030. The bulk of RAC equipment using this gas needs to be replaced in the next 5 – 10 years.

Choices need to be made about whether to do this with the carbon priced SGGs (synthetic, or ‘super greenhouse gases’) HFCs, or to use natural refrigerants like ammonia, carbon dioxide or hydrocarbons, or a new generation patented fluorocarbons the ‘HFO’s', which are also flammable, and have highly toxic thermal decomposition byproducts – currently a live issue in the European car market.

Better choices need to be made in response to demands from much more informed end users and consumers, but are currently being made by manufacturers and policy makers far removed from public attention and scrutiny.

The problem is one of attitude. Freezing inside buildings in a heat wave, or wearing shorts and T-shirt in winter, are examples of absurd human thinking, but they are almost endemic in western societies. In regard to air conditioning, we seem to have a population that apparently 'loves' summer, yet spend their every moment in an air-conditioned house, air-conditioned office, air-conditioned shopping centre, air-conditioned car or air-conditioned train, constantly trying to escape 'summer'. One finds the same fuzzy thinking when the subject of sustainable population is raised.

Just today I walked past a neighbours house along the street and the wall aircon (which faces North BTW) was on from before 9 am until after 5 pm (in Melbourne). It wasn't particularly warm most of the day but the previous night was relatively warm except for a few of the early hours when it easily cool enough but at an inconvenient time for most people.

That house could have avoided using the aircon for so long if it had had the ability to ventilate overnight using a fan or fan/duct system that uses a tiny fraction of the energy used by aircon.

But very few houses have that capability. Very few people think about this. Partly because the "experts" appear to be ideologically opposed to "forced" ventilation.